


blue tide pulling me under

by darlingargents



Category: Supernatural
Genre: Alternate Universe - Gender Changes, Codependent Winchesters (Supernatural), Consensual Underage Sex, Established Relationship, F/F, Femslash, Fluff and Smut, Plot What Plot/Porn Without Plot, Sibling Incest, Vaginal Fingering, Vaginal Fisting
Language: English
Status: Completed
Published: 2021-02-11
Updated: 2021-02-11
Packaged: 2021-03-17 13:48:49
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 2,212
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29351481
Author URL: https://archiveofourown.org/users/darlingargents/pseuds/darlingargents
Summary: “You’re so wet, Sammy. I bet I could fit my whole hand in you.”Sam’s whole body jerks. She can feel herself clenching down around Dean’s fingers, desperate, imagining herself beingfilled. Dean’s whole hand inside her. Being completely at Dean’s mercy.She has never wanted anything more in her entire life.
Relationships: Dean Winchester/Sam Winchester
Comments: 9
Kudos: 51





	blue tide pulling me under

**Author's Note:**

> Ages unspecified but Sam is about 17. I'm not counting this as Femslash February, but you know. Kind of?
> 
> Title from Shark by Oh Wonder.

It’s honestly embarrassing, how wet Sam gets for Dean.

Even before the clothes come off, when they’re making out and Dean isn’t doing anything more than grabbing her ass a bit or pushing her into the wall, she can feel it dampening her underwear. When Dean’s fingers inevitably find their way inside her underwear and slide through the slickness, Sam has come to expect that Dean will either make fun of her for being easy or get really turned on from it. Either outcome is fine.

This time is no different. Dad is gone for the weekend, no one to walk in on them, and Dean is pushing her down onto the motel bed and shoving her hand down the front of Sam’s sweatpants, rubbing her hard through her panties. Sam pants, throwing her head back against the comforter, her hands tightening in Dean’s hair. She just wants Dean closer, in every single way.

“Fuck, Sammy,” Dean says, sounding almost awed. “You’re dripping for me, baby.”

If Sam had possession of her higher faculties, she’d point out that this happens every single time. It’s not special. But she doesn’t, so she tightens her knees around Dean’s waist and rolls her hips up into Dean’s fingers. “More,” she gasps, and Dean complies.

She slides her fingers back up the seam of Sam’s cunt, to the top of her panties, and pushes inside. Her fingers slide through Sam’s pubic hair and down, grazing her clit and making her whole body jerk, and two fingers slide inside. She feels herself flushing, bites her lip as Dean works her fingers in and out, fucking her. Avoiding her clit for now, because Dean is a bitch and likes to make her wait. Draw it out.

Make her beg for it.

When Sam is squirming, desperate for more, Dean leans up to kiss her. It’s almost weirder, the kissing. The fucking feels like them; it’s an expansion of how they’ve always been each other’s whole world. But it’s weird to kiss her sister like this. Weird to know that this is romance.

Sam thinks she likes it.

Dean pulls away, her hair falling in her face and hiding its flush. Dean likes to play composure, but Sam knows she’s just as affected, that once she gets her hands in there Dean’s underwear will be as soaked as hers. Well, almost.

Dean pulls back and pulls out her fingers, and Sam bites back a whine at the loss of sensation as Dean undresses her. Sam lifts her ass off the bed and lets Dean strip her down, sweatpants and underwear and even her socks, and then Dean sits up and pulls off her shirt. She’s wearing a nice bra, a lacy black thing, probably shoplifted, and Sam can see the pink of her nipples through it. She wants to put her mouth there, so she does, sitting up and wrapping an arm around Dean’s back.

Her tongue soaks the lace of the bra and Dean gasps, a choked-off sound, as Sam scrapes her teeth along the edges of sensitive skin, runs her tongue in circles around the nipple. She pulls Dean closer with one hand, wrapped around her back. One of Dean’s hands settles in her hair, almost hesitant.

Dean still acts surprised when Sam reciprocates anything. It would be sweet if it didn’t make Sam so sad.

Sam pulls away and admires her work, the reddened and spit-slick nipple poking through lace. “I’ll have to wash that now, you bitch,” Dean says, but there’s no heat in her words, considering she’s still fighting for breath.

Sam just smiles.

Dean climbs out from between Sam’s legs and shimmies off her leggings and underwear. It doesn’t match her bra, but it’s cute, a g-string in a pale green like new leaves or Dean’s eyes. Behind it is what Sam still rarely gets to touch, somehow. The thatch of pale hair, and Sam slides her fingers through it when Dean is up on the bed again, kneeling upright. It’s trimmed, much nicer than hers.

“Fuck,” Dean gasps as Sam’s fingers circle her clit, once, twice, and move further down. She’s wet, too. Not as wet as Sam, but it’s easy enough to slide one finger in, pump it twice, slide in a second.

Dean is whimpering above her, almost, and Sam is almost dizzy with the power. She pulls her fingers back, hard, the come-hither motion that Dean does that makes her so breathless, and Dean lets out a sound that’s halfway to a shriek, curling over Sam and gripping her wrist.

“Fuck, fuck,” Dean says again, like she’s lost the ability to say anything else. “Sammy,” she manages, the second half of the word going high-pitched, and there’s a roaring in Sam’s ears like the ocean. She needs to make Dean come, she needs to see it, needs to feel it.

She fucks her fingers into Dean and rubs on her clit with her thumb, hard and rough and way too much, the way Dean likes it. Dean’s body is bent in half, her knees digging into the bed as her feet rise off, her head on Sam’s shoulder, her panting breath in Sam’s ear.

“Sammy, Sammy—” Dean says and goes rigid, her cunt clenching down as she comes. She gushes over Sam’s hand, a rush of wetness into her palm, and Sam keeps rubbing her clit and fucking her fingers in until Dean whimpers and pushes her away. Sam feels the aftershocks, Dean clenching on her fingertips, as she pulls out.

Sam’s hand is covered in Dean’s juices. She did that — she made her sister come. It makes her breathless with power.

“You have magic fingers, Sammy,” Dean managers after catching her breath. “God. Can I get you off now, please, I don’t think I pulled my weight.”

Sam laughs, and kisses her, and kisses her, and Dean pushes her down on the bed and slides three fingers in Sam’s cunt. Sam is even wetter now, somehow, because watching Dean come like that was probably the hottest thing she’s ever seen, and Dean’s fingers go easy. She breaks out of the kiss, moves her head down, and licks Sam’s clit, swirling her tongue around it like it’s a lollipop. She’s smiling when she looks back up at Sam, lips shining like she’s wearing lipgloss.

“You’re so wet, Sammy. I bet I could fit my whole hand in you.”

Sam’s whole body jerks. She can feel herself clenching down around Dean’s fingers, desperate, imagining herself being  _ filled _ . Dean’s whole hand inside her. Being completely at Dean’s mercy.

She has never wanted anything more in her entire life.

“Please,” she says, and something in her tone must be convincing, because Dean is staring at her with shock and unfiltered arousal. Her pupils are blown so wide Sam can’t see the colour of her eyes.

“You want — god, Sammy, okay.” Dean leans down to lick her clit again, slow and sweet, and lifts her gaze again. “Okay. Let me know if it hurts, okay?”

Sam nods, desperate. She knows it’s going to hurt, but suddenly it’s the most important thing in the world. Dean inside her. As close as they can possibly be.

Dean works her three fingers in and out, the slick noises loud in the quiet of the motel room. Sam is still getting wetter, somehow, and she swears they’ll need to change the sheets or something, because it’s almost a goddamn puddle.

Then Dean adds her pinky, sliding all the way down, and Sam loses her coherent train of thought.

She’s never been this full before, she’s sure of that. Even when she was younger and went through a phase when she just wanted to fuck herself with whatever she could find — the handle of her hairbrush, a shampoo bottle, even a water bottle once. (Dean had decided to give her a sex ed talk sometime around then and it had scared her out of the habit. Her fingers were good enough. And later, Dean’s fingers.) The point is — this is more, and it’s so much better. Dean isn’t doing much, just sliding her four fingers in and out, but it sends bursts of pleasure through her whole body. Words are entirely beyond her; if Dean stopped, she wouldn’t even be able to yell at her. All that’s coming out of her mouth is a litany of gasps and moans and the occasional  _ fuck _ or  _ Dean _ .

“God, you feel so good,” Dean says, and Sam has to close her eyes, because seeing Dean’s face along with hearing her talk and feeling her inside is too much for her to handle. “So fucking tight for me. So wet. You can take all this, right?”

Sam nods, frantic. If Dean stops now she’ll never forgive her.

Dean pulls her fingers back, slow and deliberate, and pushes in her thumb.

Sam’s eyes roll back in her head. Her hands flail for something to hold onto, ending up clutching the bedspread in one hand and Dean’s hair in the other. She needs to hold on, because she feels like she might float away or twitch out of her body.

Dean is breathing hard as she pushes in all five fingers, down to the widest part of her hand. It hurts, in the best way possible, and Sam forces herself not to clench down as Dean’s knuckles pass through the opening, forcing her wide open. There’s a moment of real pain, enough that Sam feels her eyes start to water and bites down on her lip. Then it pops past, and Dean slides all the way in.

“Fuck,” Dean says, her voice low and almost worshipful. “I’m… I’m  _ in _ you, Sammy.”

Sam tugs gently on the hand tangled in her sister’s hair. “Yeah,” she says, breathless. “Yeah, god.”

“Can I—“ Dean stops, takes a deep breath. She’s never like this, never so overwhelmed and hesitant, seeming almost insecure. Sam knows she wasn’t her sister’s first for anything, and she’s mostly made her peace with the difference between them in that regard, but she doesn’t think Dean has ever done this. They’ve on even ground.

It’s intoxicating.

“Move,” she says, and Dean pulls her hand back. Her knuckles catch on the rim of Sam’s cunt and there’s that flash of pain again. She welcomes it, bites down and pulls Dean’s hair and gasps “Don’t stop,” because Dean still hates anything that causes her pain. Dean swallows, audible, and pushes her hand back in. Hard. 

It shakes Sam to the core, a spike of pleasure-pain jolting her whole body from Dean’s hand in her cunt to the tips of her fingers. Her back arches off the bed and she can’t hold back the cry that tears out of her throat. She’s so  _ full _ , completely filled up with her sister.

Dean keeps her hand moving, again and again, until Sam is totally lost in the sensation. Everything else has faded away. There’s just Dean’s hand in her cunt, Dean telling her how pretty she is and how well she’s taking it. Something touches her clit and she jerks, overstimulated already, but Dean keeps going, thrusts her hand and rubs Sam’s clit the way she likes and Sam is coming like she never has before. Everything goes white, her whole body shakes like she’s having a seizure, she can feel herself clenching around the ridges of Dean’s hand inside her. And it just keeps going, and going, and going—

When she finally comes down, Dean’s hand is out of her, just two fingers still inside and gently rubbing.

“You good?” Dean asks. She’s moved from between Sam’s legs to the bed next to her, and the hand that’s not inside her reaches up to brush a bit of hair out of Sam’s eyes.

“Yeah,” Sam says, and reaches up to wipe away the tears in her eyes. When Dean gives her a worried look, she laughs a little. “Good tears. Promise.”

“Okay, okay.” Dean pulls her fingers out and lifts her hand. It’s dripping. Sam is pretty sure there’s a real puddle under her ass by this point. “I think you passed out from screaming too hard.”

“If we get a noise complaint, you can deal with it. I’m not moving.” Sam flops an arm over her eyes. “I’m just gonna sleep here.”

Dean pulls her arm away from her face and leans in to kiss her. It’s a surprisingly chaste kiss, just a soft press of lips, and it makes Sam smile before Dean even breaks away.

“I’ll run you a bath,” Dean says. “I think I have some bubbles somewhere.”

Sam still doesn’t want to move for the next year, but… “Fine. I’m not gonna move until it’s ready, though.”

Dean rolls her eyes and gets up, stretching her arms over her head and reaching for a shirt. “Okay, princess.”

“Bitch.”

Dean just blows a kiss over her shoulder and goes into the bathroom. Sam hears the tap start to run, and a minute or so later, she can smell the vanilla from Dean’s bubble bath.

She rolls over and smiles into the sheets. She’s still sore, so goddamn sore, and she knows she’s gonna feel it tomorrow, but Sam doesn’t think she’s ever been happier.


End file.
